1. Field of the Invention
The present invention relates to an apparatus and method for the processing of food. In another aspect, the present invention relates to an apparatus and method for the extraction of edible products from crawfish and other crustaceans. In even another aspect, the present invention relates to a labor saving apparatus and method that consistently removes the intestinal track from whole crawfish while neither wasting nor damaging the tail meat.
2. Description of the Related Art
The Wall Street Journal, May 7, 1996, documents the "epic quest" in which tinkerers have been laboring in South Louisiana garages, machine shops and seafood houses for more than 20 years pursuing the elusive goal of inventing a contraption that will separate the small but well armored crawfish from their tender tail meat. The Wall Street Journal further notes that with the industry's future now hanging in the balance, the "quest" has taken on an almost epic proportions in Louisiana, where most of the nation's crawfish are harvested and eaten.
The story of the development of a crawfish peeling machine is one of long felt need coupled with numerous failures by others.
Crawfish and similar crustaceans are becoming an increasingly popular food in the United States and abroad. Typically, in the Texas Gulf Coast area, larger crawfish are boiled in spices then individually peeled and eaten by the diner.
The normal method of eating a crawfish, requires that the crawfish meat be removed from the shell, and involves breaking the crawfish, and removing the head piece which contains little edible matter, straightening the shell with the fingers, removing the two rings closest to the head and attempting to squeeze the shell, much in the manner of squeezing a tube of tooth paste from the bottom.
However, not all crawfish are peeled and eaten by the diner. For example, peeled crawfish tails are required for use in such dishes as crawfish bisque, crawfish etouffe, fried crawfish tails and the like. However, there are several problems currently associated with the commercial preparation of peeled crawfish tails.
High labor costs, for example, make commercially processed peeled and packaged crawfish tails expensive. Peeling crawfish by hand is very labor intensive and time consuming. While a crawfish appears to resemble a lobster, it is a much different animal, being many, many times smaller. Thus, the hand peeling method typically associated with lobsters becomes very time consuming and labor intensive when applied to crawfish because the yield is so small for the time invested. For example, an experienced worker can peel and de-vein a crawfish tail in about three seconds, but the work is tough and tedious. This is especially true in the colder months when the shells of crawfish are hardest. To compound the problem of high domestic labor costs, there has been an influx of lower priced imported peeled crawfish tail meat.
Producers of crawfish in the United States, are and for some time have been searching for a labor saving machine that is able to peel crawfish tails. However, the problems associated with such devices involve the removal of the intestinal tract of the crustacean while leaving the tail meat intact.
A viable labor saving crawfish peeler therefore must be able to consistently remove the intestinal track, sometimes called the "sand" or "mud" vein, while neither wasting nor mangling the delicate tail meat. Such a device must be able to efficiently and effectively uncurl the tail of cooked crawfish, remove the head, and be able to accommodate crawfish of all sizes and shell hardnesses.
There have been numerous attempts in the prior art to automate crawfish peeling.
U.S. Pat. No. 3,110,926, issued Nov. 19, 1963 to Martin discloses an apparatus and process for the treatment of crustacea such as crawfish, prawns and the like, to clean out the contents of the black vein, or sand sac, from the tail portions and render it ready for marketing as processed products for human consumption. The contents of the vein are flushed or sluiced out by fluid pressure introduced into one end of the tail. The '926 device, however, does not remove the crawfish head and requires two steps to extract the tail meat from the exoskeleton, one to remove the vein contents, the other to remove the tail meat.
U.S. Pat. No. 3,221,363, issued Dec. 7, 1965 to Couret discloses a process for removing the edible meats from crustacea tails, and has for an object to provide a method for removing the edible meat from the Dublin Bay prawn, which is commercially known as scampi. The meat is de-veined while the meat is still in the prawn shell by boring adjacent to the vein to sever the vein from contact with the shell and applying negative pressure to the hollow bore of the boring instrument to draw off the severed vein from the meat. Fluid pressure then ejects the meat from the shell. The '363 device, however, does not remove the crawfish head and requires two steps to de-vein the tail meat, one to sever the mud vein and the second to remove the vein by vacuum pressure. Severing the vein increases the likelihood of spilling its contents and/or leaving portions of the vein attached to the meat.
U.S. Pat. No. 3,278,983, issued Oct. 18, 1966 to Martin discloses an improved process for the removal, or flushing out, of the black vein and for removing the flesh in on one piece from the severed tail portions of crustacea. The crustacean are fed tail first to a water nozzle applied to the anus for the flushing out of the sand sac and then to an air nozzle inserted into the tail for ejection of the flesh from the shell. This '983 device is a refinement of the '926 device and suffers from the same drawbacks.
U.S. Pat. No. 3,758,921, issued Sep. 18, 1973 to Ingalls discloses a machine for automatically peeling crawfish or other crustaceans in which the crustacean to be peeled has its head and tail respectively held between grippers on separate conveyors having operative runs which diverge in the direction of their movement. The grippers of the two conveyers are in laterally opposed pairs which are located abreast of and adjacent to each other at the loading ends of the conveyers to receive the head and tail sections respectively of the crustacean and thereafter to separate the head and tail sections as they move apart due to the divergences of the operative conveyer runs, with the meat remaining in the tail section. The meat retained in the tail section is ejected by shearing off the extremity of the tail section incident to movement of its associated conveyer, then injecting a blast of pressurized air into the tail section through the opening formed by such shearing operation. The '921 device simply blows the tail meat through a tunnel created by removing the head and severing the tail. The '921 device makes no reference to the consistent removal of the sand vein.
U.S. Pat. No. 3,789,460, issued Feb. 5, 1974 to Ingalls discloses pairs of grippers for operative engagement with the tail and head ends respectively of a crawfish where the grippers are supported for movement in synchronized relation through separate but tangentially related orbits wherein both pairs of grippers simultaneously move in a common direction through or past the point of tangency of their respective orbits. Thus a crawfish, the tail of which is placed in the tail grippers with its head projecting therefrom, will be carried toward the point of tangency to place its head in the head grippers, which will then be closed approximately at the point of tangency to then remove the head during continued movement of both pairs of grippers through and past the point of tangency, leaving the meat within the portion retained in the tail grippers. A nozzle which penetrates the tail section of the shell, then injects a blast of air into the shell to eject the meat. The deveining pin on which the shell and meat are impaled when initially placed in the tail grippers, functions to open and remove the sand vein from the crawfish incident to its ejection under the influence of the air blast. The '460 device does remove the crawfish head but requires the tail to be manually straightened. The '460 device attempts to remove the sand vein by means of a pin which splits the meat and sometimes destroys the integrity of the vein spilling its contents. In addition, the '460 device requires hand separation of the meat from the vein.
U.S. Pat. No. 4,196,495 issued Apr. 8, 1980 to Mestayer et al. discloses an apparatus for separating edible tail portions of crawfish and similar crustaceans from exoskeletal portions thereof, the '495 invention comprises a first roller having a concave lateral peripheral edge surface which is opposed at a substantially constant spacing by a convex lateral peripheral edge surface of a second roller, the rollers being rotated in opposite senses to receive the exoskeletal portions of the crawfish between the opposing peripheral edge surfaces of the rollers. Rear margins of the flippers of the crawfish are grasped between the counter rotating rollers, the exoskeletal portions covering the tail being pulled between the rollers to peel said exoskeletal portions from the edible portions and to simultaneously deveining the crawfish tail. The '495 device removes neither the crawfish head nor the sand vein. In addition, the '495 device does not work on cooked crawfish.
U.S. Pat. No. 4,385,422, issued May 31, 1983 to Ingalls, deceased et al. discloses an improved apparatus for deheading and peeling crawfish comprising pairs of gripper assemblies for operative engagement with the head and tail sections of a crawfish, respectively, supported for movement in synchronized relation through separate but tangentially related orbits wherein the pairs of grippers simultaneously move in a common direction through or past the point of tangency of their respective orbits wherein the tail holding gripper assemblies each comprise a lower crawfish pan constructed from flexible rubber or plastic having an arcuate cross section greater than 180.degree. and a top arm pivotly mounted above the lower pan to hold the crawfish in the pan during the deheading cycle the pivoting of the top arm being actuated by a simplified cam assembly. The, '422 device does not provide any means for removing the sand vein, nor adequately allows for different sizes of crawfish.
U.S. Pat. No. 4,928,352, issued May 29, 1990 to Thibodeaux discloses a crawfish peeling apparatus for separating the crawfish upper and lower tail exoskeleton portions from the soft inner meat product including a frame that supports a feed mechanism for advancing crawfish tails to be peeled along a travel path that traverses a cutter. The cutter includes preferably a pair of spaced apart rotary blades, each pair overlapping in a scissoring fashion so that longitudinal edge cuts can be made along the left and right sides of the crawfish tail and extending substantially the full length of the crawfish tail. The '352 device does not remove the crawfish head and works only on raw crawfish.
U.S. Pat. No. 5,055,085 issued Oct. 8, 1991 to Thibodeaux discloses a crawfish peeling apparatus uses fluid under pressure flowing through a tool body to a lance that punctures the crawfish exoskeleton. Fluid exits the tool body at the lance and travels into the crawfish exoskeleton at the lance and forces the tail meat from the exoskeleton tail portion. The '085 device is not automated, does not remove the head and does not remove the vein.
Despite the advances of the prior art, there still does not exist a crawfish peeling apparatus which is able to uncurl the cooked crawfish tails of all sizes, snap such crawfish tails off the body, and then extract the delicate meat inside and pull out the tiny intestinal tract. For example, none of the above patents to Thibodeaux are capable of separating the intestinal vein from the tail meat. In fact, in the May 7, 1996 Wall Street Journal Article, Mr. Thibodeaux notes, "if it weren't for that vein, I'd be rich." In further testament to the difficult nature of devising a crawfish peeling apparatus which will remove the intestinal vein from the tail meat, the Wall Street Journal further notes that Mr. Thibodeaux has spent 10 years and nearly $50,000.00 searching for a viable peeler.
This same Wall Street Journal article further notes that a machine based on the Ingalls, several of which are referenced above, have also commercially failed.
Therefore there is a need in the art for a crawfish peeling apparatus and method that does not suffer from the deficiencies of the prior art.
There is another need in the art for a crawfish peeling apparatus and method that is more efficient, but just as effective as hand peeling.
There is even another need in the art for a crawfish peeling apparatus and method that is able to consistently remove the intestinal track, while neither wasting nor mangling the tail meat.
There is yet another need in the art for a crawfish peeling apparatus and method that is able to accommodate crawfish of all sizes and shell hardnesses.